Aberrant behaviors, i.e. self-injury, aggression, and stereotyped behavior, are some of the most devastating neurodevelopmental disorders (ND). They lead to deteriorating health and, sometimes, early death;they prevent community integration;they impair learning and socialization opportunities;and they are the most salient reason for job failure in the community. They are often linked to several gene-brain-behavior dysfunctions. Prevalence estimates of ND in the U.S., UK, and Europe average c.10% in total population studies. Among all people with ND, prevalence studies in these countries estimate approximately 10-25 % have severe aberrant behaviors, but prevalence is unknown in Latin American countries. Extensive research on behavioral and psychopharmacological treatment and prevention exists, but not in Latin America, where this population is severely underserved. This project aims to study the development and prevention of aberrant behaviors of people with ND in Peru (population 22 million), where only 2% of the population of an estimated 3 million people who have ND are being served. The Centro Ann Sullivan Center del Peru (CASP) is a state-of-the-art school for neurodevelopmental disorders based in Lima, with a network of satellite programs in Peru, Argentina, Brazil, Bolivia, Colombia, Guatemala, Nicaragua, Ecuador, and Spain. CASP has a 27-year history of collaborative sponsorship with the Life Span Institute at the University of Kansas In response to Fogarty PAR-08-113, we propose an R21 to screen 1000 infants and toddlers expecting to find 250 who are at risk for ND, 6-36 mos., 50% of whom are also likely to be at risk for aberrant behaviors (AB) and to follow 100 or more of them plus 100 or more matched controls with ND, but not at risk for AB, at 6- month intervals for 12 months with in-depth interdisciplinary evaluations involving pediatric, psychoeducational, behavioral, neurological, and genetic assessments, to see if they develop aberrant behaviors, as was shown in the U.S. by Berkson, et al.( 2002). The results of this early identification program will be followed by a 5-year R01 on early preventive intervention of aberrant behavior in infants and young children with ND in Lima, Peru. The R21 will also concentrate on building on the existing excellent psycho-educational program and distance learning network at CASP by adding research infrastructure, increasing the research capacity of staff, translation and validation of assessment instruments, and collaborations with appropriate investigators in universities in the U.S., Peru, and other Latin American countries, who will then participate in the subsequent R01. There may be differences in the development of aberrant behavior due to sociocultural practices and health issues, such as uncontrolled environmental pollution, in Latin America. PUBLIC HEALTH RELEVANCE: This project concerns the gene-brain-behavior relationships involved in the development of aberrant behaviors among infants and young children with neurodevelopmental disorders (ND) who live in high-risk environments in Lima, Peru. We plan to develop a risk algorithm that will permit a cost-effective effort at early preventive intervention that can be replicated throughout Latin America, across the CASP distance learning network and beyond, for young children with these extremely debilitating problems.